【摘要】 为研究控制排水措施对土壤硝态氮运移和转化的影响,通过测坑试验分析了不同控制排水位下土壤不同深度硝态氮的含量和分布。结果表明:①控制与非控制排水条件下土壤剖面硝态氮分布规律相似,硝态氮含量集中在0～40 cm土层,深层土壤中硝态氮浓度很小在1 mg/kg左右,不会污染地下水;②排水结束后至降雨前,表层至40 cm土壤剖面硝态氮浓度变化率和各田硝态氮含量的增大率与控制排水出口的高度成负相关,降雨至排水结束后,表层硝态氮的浓度均减小,表层以下硝态氮浓度变化与地下水埋深有关,地下水位以上硝态氮浓度一般增大,地下水位以下硝态氮浓度一般减小。结论为控制排水措施减小了深层土壤硝态氮含量,且大大减少了土壤中硝态氮的含量,且控制排水能有效减少硝态氮的流失量。更多还原

【Abstract】 A leaching-pond experimental project is set up to research the effect of different controlled water level on the soil nitrogen transport-transformation. Through observing and analyzing the soil nitrate nitrogen content along the soil profile, This paper concludes that: ① the nitrate nitrogen content distribution in soil shows similarities under different controlled water level, the main nitrate nitrogen concentration is in the 0～40 cm soil, and it is about 1 mg/kg in deep soil. ② The nitrate nitrogen concentration decreases in 0～40 cm soil as the height of drain outlets increases after rain, and it all decreases in topsoil in rain, besides, it generally increases above the ground water and decreases below the ground water in soil. The headline conclusion is that the drainage control plays a significant role in the loss of the nitrate nitrogen in soil.更多还原